Model output discussion - late November

[ItNeverSnowsInWindsor]

Does anyone knowledgeable know what might be causing the models to churn out colder runs in the medium range like the GFS 12z op for next mid-week ?

I thought the background signals weren’t conducive for such cold spells in December.

[Tim Bland]

Cold all the way down to Africa with most of Spain covered in snow 

[Skullzrulerz]

3 minutes ago, Mapantz said:

That's a nice chart for December 11th, but I wouldn't quite want it to pan out like that. The heaviest of the precip stays out in the channel and it moves through extremely fast, so it wouldn't give any meaningful accumulations.

It's academic, of course, but still nice to see!

At least cornwall hits the jackpot! About time we see a decent snow event down here

A Incredible GFS 12z run though if only it could happen...hopefully it could be a start of a trend? 

[feb1991blizzard]

BOOM!

[Allseasons-Si]

Just now, feb1991blizzard said:

Here comes 5th Feb 1996 signature.

I want a Feb 1991

this dropping down from the NW could be fun too with cold air over the uk.

JFF but i would like to see  where this run sits in the ens.

 

 

[Ice Day]

1 minute ago, Mucka said:

Yes but arguably the building blocks are in place by day 8 for a cold spell so not super FI

Let's see what that eCM brings

Exactly, I would say that from 174 the pattern was only going one way..... cold!

So not deep FI at all (although some would argue that 120 is FI on the GFS )

[That ECM]

1 minute ago, Ice Day said:

Exactly, I would say that from 174 the pattern was only going one way..... cold!

So not deep FI at all (although some would argue that 120 is FI on the GFS )

Ukmo at t144 is different to gfs. Not hugely but different. Now would ukmo go on to be like gfs? I don’t think so due to the angle of low but I’ll let @Steve Murr and others comment.

[Ali1977]

What a great 12z from the GFS, starting around day 8 with a cold spell (possibly very). Also great for the skiing industry in Scotland , and the alps look to have another epic week of falls next week. 

[SMU]

6 minutes ago, That ECM said:

Ukmo at t144 is different to gfs. Not hugely but different. Now would ukmo go on to be like gfs? I don’t think so due to the angle of low but I’ll let @Steve Murr and others comment.

Will review UKMO 168 later - it was a smidge flatter ...

[I remember Atlantic 252]

23 minutes ago, Allseasons-si said:

My word!!!

day ten

hello @pv

dropping to lower lat's.

great 12z.

 

vote in our woolies! and Scottish folk snowed in at elevation

[Ali1977]

Day 10 mean shows no sign of heights around Greenland, so although decent over the U.K. the Op looks like a cold outlier. 

[Tim Bland]

Would be nice to have ECM and GEM on board later for the day 10 cold spell as neither are very interested at the moment

[Tim Bland]

7 minutes ago, Ali1977 said:

Day 10 mean shows no sign of heights around Greenland, so although decent over the U.K. the Op looks like a cold outlier. 

It indicates a massively displaced Azores high and Atlantic ridge though? I’d say a majority of members still have a flow north of west at least

[booferking]

9 minutes ago, Ali1977 said:

Day 10 mean shows no sign of heights around Greenland, so although decent over the U.K. the Op looks like a cold outlier. 

Have to say it looks very good to me MCslider like the op.

[Ali1977]

6 minutes ago, Tim Bland said:

It indicates a massively displaced Azores high and Atlantic ridge though? I’d say a majority of members still have a flow north of west at least

Defo plenty with a northerly flow but the area around Greeny is very diff on the ENS compared to Op. hopefully ECM backs the Op again.

Edited December 2, 2019 by Ali1977

[booferking]

GEM decent

[Tim Bland]

A mean will never look like the op at day 10+. Imagine 9 white cars and 1 black cars..the mean is grey. It only takes a couple of ensembles to wash out the majority 

[Allseasons-Si]

The mean is gaining momentum >-5 from the 11th and the op has some support.

[Tim Bland]

9 minutes ago, booferking said:

GEM decent

Jet not digging south and no sliding lows on the GEM still unfortunately. Doesn’t have the wedge of heights in Greenland unfortunately. 

[ItNeverSnowsInWindsor]

3 minutes ago, Allseasons-si said:

The mean is gaining momentum >-5 from the 11th and the op has some support.

Looks like an outlier to me with just the odd one interested.

[Tim Bland]

3 minutes ago, prolongedSnowLover said:

Looks like an outlier to me with just the odd one interested.

Depends how you define ‘interested’ ? Mean T850hpa is near -5c now @ day 10 which is all that is needed (near the shortest day ) for snow. Op is one of the coldest. Personally I just like snow. 2c and snow is good enough for me! 

[Purga]

Nice bit of snow for Surrey & Sussex - for once!

[booferking]

9 minutes ago, Tim Bland said:

Jet not digging south and no sliding lows on the GEM still unfortunately. Doesn’t have the wedge of heights in Greenland unfortunately. 

It wont jump in one run this Mornings vs Evenings i will take the small steps for trends.

[MR EXTREMES]

1 hour ago, Steve Murr said:

Take it to the bank :0

Thing is though still way out in lala land. But always a possibility 

[Methuselah]

Well, at least the 12Z operational isn't technically an outlier -- though it is very-much on the colder end of the pack:

   

   

So, there at at least several cold 'options'...all of which, Mr. Weather choose will ignore!